26. If the principal quantum number of an electron is n = 4, how many possible values of the orbital magnetic quantum number ml are there for this electron?

29. A strong bar magnet is held very close to the opening of a solenoid as shown in the diagram.

 

 

As the magnet is moved away from the solenoid at constant speed, what is the direction of conventional current through the resistor shown and what is the direction of the force on the magnet because of the induced current?

 

30. A light beam passes through the air and strikes the surface of a plastic block. Which pair of statements correctly describes the phase changes for the reflected wave and the transmitted wave?

 

31. For the circuit shown, ξ = 6.0 V, R₁ = 7.0Ω, R₂ = 3.0Ω , R₃ = 6.0Ω , and R₄ = 12.0Ω . After operating for a long time, equilibrium is established.

 

 

What is the voltage across the capacitor at equilibrium?

 

 

Two point charges are fixed on the x-axis in otherwise empty space as shown below.

 

 

33. In which Region(s) is there a place on the x-axis (aside from infinity) at which the electric potential is equal to zero?

 

35. Astronauts on the Moon perform an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in the diagram with 0° < θ < 90°, the total acceleration of the mass may be directed in which of the following ways?

 

36. An electron moves in the plane of the page through two regions of space along the dotted-line trajectory shown in the figure. There is a uniform electric field in Region I directed into the plane of the page (as shown). There is no electric field in Region II.

 

 

What is a necessary direction of the magnetic field in regions I and II? (Ignore gravitational forces.)

 

37. A uniform meter stick has a 45.0 g mass placed at the 20 cm mark as shown in the figure. If a pivot is placed at the 42.5 cm mark and the meter stick remains horizontal in static equilibrium, what is the mass of the meter stick?

 

40. A point particle of mass m collides with a thin rod pivoted at one end. The rod has mass M = 2m, length L, and moment of inertia I = 1/3 ML² . The particle moves horizontally with speed V when it hits the bottom of the rod and sticks to it.

 

 

What is the speed of the particle immediately after collision?

 

 

41. The circuit shown has been operating for a long time. The instant after the switch in the circuit labeled S is opened, what is the voltage across the inductor V_L and which labeled point (A or B) of the inductor is at a higher potential? Take R₁  = 4.0Ω, R₂  = 8.0Ω, and L = 2.5 H.

 

43. Unpolarized light of intensity I₀ enters a polarizer-analyzer system in which the angle between the transmission axes of the polarizer and analyzer is 30º. What is the intensity of the light leaving the analyzer?

48. A block of mass M on a horizontal surface is connected to the end of a massless spring of spring constant k. The block is pulled a distance x from equilibrium and when released from rest, the block moves toward equilibrium.

 

 

What minimum coefficient of kinetic friction between the surface and the block would prevent the block from returning to equilibrium with non-zero speed?

50. An infinitely long solenoid passes through the circuit as shown. The magnetic field of the solenoid, directed into the plane of the page, is weakening which produces a constant emf of magnitude ξ for a closed loop around the outside of the solenoid.

 

 

Once equilibrium is established in this circuit, what is the voltage across the switch S?